While I agree with you that the bloat problem gets painted larger than it really is, your solution isn't easily implemented. Say you want to build a 3.x character able to use a spear to throw his opponents prone. Which search query would yield the feats necessary for this?
If you have a concept in mind search is probably not enough, because you don't know the relevant terms. It's great to decipher a character sheet, though.
Not "easily implemented"? Well, I agree in the sense that it requires good data entry, programming and so on to make a system that makes finding such a thing easy! 4E
has that, though. So long as 5E is as good as 4E's DDI (hopefully better), it would be trivial to find such a thing.
I agree that with 3.5E/PF it's harder because it's all just on the web (and not in one place with 3.5E), not properly indexed.
I would say, though - would you even have that concept in mind if you didn't know such a Feat or Feat-chain existed? I think not!

So you would have some basis for your searching.
The problem is, we have basically a binary scenario here, I think:
1) WotC-enforced no-bloat: WotC refuses to publish any game mechanic material in Dragon, and only produces a handful, tops, of books containing any mechanics over the entire lifespan of the edition (i.e. 1E model, no?)
Obviously that's not profitable for WotC, and it's disappointing for the significant section of the RPG/D&D market who actually likes new material, who will likely turn to 3PPs and/or other RPGs entirely as a result -leading to poor-quality 3PP material likely being more popular than otherwise and less money in WotC's pockets.
2) WotC produces stuff some people will insist is "bloat" - Dragon has mechanics sometimes, books come out fairly regularly with mechanics in them.
In this case, WotC, I suspect, makes a lot more money, fans, I suspect, are a lot happier overall, because they can choose whether to "bloat" or not, and people are less likely to go to 3PPs or other RPGs.
2 can also be mitigated with good digital tool/product design, a la 4E but better.
I mean, am I wrong? Would only releasing 1E numbers of books make WotC more money, in 2014? I'm skeptical of that, I must say.